Most parents put far more toothpaste on a child's brush than the child needs. The amount that protects young teeth is small: none at all before 18 months, then just a thin smear, rising to a pea-sized amount when the strength of the paste changes at age six. Smaller amounts are not a compromise. They are what Australian fluoride guidance actually recommends.
Three age bands, two kinds of toothpaste
Australian guidance on fluoride use splits childhood into three stages. The amount stays small throughout. What changes is whether toothpaste is used at all, and how much fluoride it contains.
| Age | What to use | How much |
|---|---|---|
| Birth to 17 months | No toothpaste, a soft brush and water | Nothing on the brush |
| 18 months to 5 years | Low-fluoride children's toothpaste (around 500 ppm) | A smear |
| 6 years and older | Standard fluoride toothpaste (1000 to 1450 ppm) | A pea-sized amount |
"ppm" means parts per million, and it is printed on the tube, sometimes as mg/g (0.5 mg/g is the same as 500 ppm). A toothpaste without fluoride will not give the protection described here, so check the label for the fluoride content.
Before 18 months, water is enough
Cleaning starts when the first tooth comes through, usually somewhere around six months. A small, soft toothbrush or a clean damp cloth, twice a day, removes plaque and gets your baby used to the routine. Toothpaste is not part of the routine yet for most babies. The exception is a child your dentist or OHT has assessed as being at higher risk of decay, who may be advised to start fluoride toothpaste earlier. Our guide to cleaning baby and toddler teeth covers positions and technique.
From 18 months, a smear of low-fluoride paste
At this age a child swallows much of whatever goes in their mouth, so the paste is weaker and the amount is kept to a thin smear across the bristles. Brush in the morning and again before bed. Toddlers and preschoolers do not have the hand control to clean properly, so an adult should do the brushing, or at least finish it off.
From six, the family toothpaste
Once a child turns six they can switch to a standard fluoride toothpaste, the same type adults use, in a pea-sized amount. By this age most children can spit out reliably, and the first permanent molars are usually arriving, so the higher strength gives those new teeth better protection. Keep watching or helping until you are happy they reach every surface, which for many children is around seven or eight.
Why a little fluoride goes a long way
Fluoride makes enamel more resistant to acid and helps repair the earliest, chalky stage of decay before it becomes a hole. It does this best when a small amount stays in the mouth after brushing.
The reason for keeping amounts small in young children is fluorosis. If a child regularly swallows more fluoride than they need while their adult teeth are still forming under the gums, those teeth can come through with faint white flecks or lines. In Australian children it is usually very mild, and a South Australian follow-up study found mild fluorosis tended to fade over time and did not affect how people rated their oral health. Using the right amount avoids it without giving up the protection. Our article on whether fluoride is safe for teeth explains the evidence on this balance.
Spit, and skip the rinse
After brushing, have your child spit out the extra toothpaste but not rinse with water. A rinse washes away the fluoride that would otherwise keep working on the enamel for some time. The night-time brush matters most, since saliva flow drops during sleep. After that brush, only water until morning.
Young children often cannot spit at first. That is expected, and it is the reason the amount is kept so small. Keep the tube out of reach so toothpaste is not eaten as a treat.
When the standard advice changes
These amounts suit most children. Some children have a higher chance of decay because of earlier cavities, frequent snacking, a medical condition, or teeth that are hard to clean. For them, your dentist or OHT may suggest starting standard toothpaste earlier, or adding professionally applied fluoride varnish. That is a decision made after looking at the child's teeth, so it is best not to change strengths on your own.
Toothpaste is also only one part of protecting young teeth. How often sugary food and drinks appear through the day has a large effect, and our article on tooth-friendly snacks for children deals with that side. The wider picture of how decay starts and how to stop it is in our guide to cavity prevention.
Common questions
My toddler swallows the toothpaste. Should I worry?
Swallowing a smear of low-fluoride paste is expected at this age and is not harmful. The small amount is chosen with swallowing in mind. Problems only arise with regular use of much larger amounts.
Can my four-year-old use my toothpaste?
Standard toothpaste is generally recommended from age six. Before then, a low-fluoride children's paste is the usual advice unless your dentist or OHT has recommended otherwise for your child.
My child has white marks on their teeth. Is that from toothpaste?
It might be, but white marks can also come from early decay or from enamel that formed differently. They look similar and need different handling, so it is worth having them checked rather than guessing.
Our oral health therapists see children from their first teeth onward, and a first dental visit is a good time to ask about the right toothpaste for your child. To book, see our current offers or visit our family dentist page for Melrose Park.
